It's a chilling thought. In the coming year, 130,000 people worldwide will suffer spinal-cord injuries—in a car crash, perhaps, or a fall. More than 90 percent of them will endure at least partial paralysis. There is no cure. But after a decade of hype and controversy over research on embryonic stem cells—cells that could, among other things, potentially repair injured spinal cords—the world's first clinical trial is about to begin. As early as this month, the first of 10 newly injured Americans, paralyzed from the waist down, will become participants in a study to assess the safety of a conservative, low-dose treatment. If all goes well, researchers will have taken a promising step toward a goal that once would have been considered a miracle—to help the lame walk.The trial signals a new energy permeating the field of stem-cell research. More than 3,000 scientists recently met in Barcelona for the annual conference of the International Society for Stem Cell Research, compared with...

Who wouldn't love to find a drug to help prevent or at least delay the onset of Alzheimer's disease? It turns out that one may already exist. Dr. Benjamin Wolozin, professor of pharmacology at Boston University School of Medicine, posted a study this week in the online journal BioMed Central Medicine showing that the cholesterol-lowering drug Zocor (simvastatin) reduced the incidence of both Alzheimer's disease and Parkinson's by about 50 percent in a population of 4.5 million veterans over a three-year period. By comparison, two other statin drugs—Lipitor (atorvastatin) and Mevacor (lovastatin)—showed little or no effect.Before you rush to your doctor, be aware that it's too early to draw clinical recommendations from the new findings. This was a broad observational study rather than a gold-standard randomized clinical trial, in which all the variables are carefully controlled. "At least one, sometimes two, randomized clinical trials would be required before the FDA would approve...

When Jan Luedecke of Toronto was arrested and tried for sexual assault, he had an unusual defense—he did it in his sleep. Really. It may sound farfetched, but Luedecke, who was 33 at his 2005 trial, had a history of sleepwalking. On the night in question, he'd been drinking at a party and found himself sacked out on the couch with a woman he'd met there. Hours later, she jolted him awake and demanded to know what he was doing. Luedecke claimed he was unaware he was having sex with her. "Under the law, if there's no intent to commit a crime, you haven't committed a crime," says Dr. Colin Shapiro, director of the Youthdale Child and Adolescent Sleep Center in Toronto, who testified for the defense. Luedecke was acquitted (to the outrage of women's organizations in Canada), and the case is now on appeal.Add sex to the roster of unlikely sleep behaviors known as parasomnias, which range from sleep driving to sleep eating. Last week psychiatrist Carlos Schenck and neurologist Mark...

The common white sucker is nobody's favorite fish. It's a bottom feeder that trout fishermen in Colorado happily toss back into the water. But it's also what scientists call a sentinel—a species whose health (or lack thereof) can warn us about problems in the environment. So imagine the reaction of environmental endocrinologist David O. Norris of the University of Colorado when he discovered some alarming changes in the sucker population of Boulder Creek. Upstream, where the water flows pure and clear out of the Rocky Mountains, the ratio of males to females is 50-50, just as nature intended. Downstream, below the wastewater-treatment plant in Boulder, the females outnumber the males by 5 to 1. Even more worrisome, Norris found that about 10 percent of the fish were neither clearly male nor female, but had sexual characteristics of both. "On the one hand, we were excited [to make such a dramatic finding]," says Norris. "At the same time, we were appalled."There's something fishy in...

Prostate cancer is the second leading cancer killer among men, after lung cancer. The American Cancer Society projects that in 2007 there will be 219,000 new cases and 27,000 deaths. Yet detecting the disease early has always been problematic. The only blood test available now—a test for prostate-specific antigen (PSA)—is not good at distinguishing malignancies from benign prostate enlargement (BPH). And it's useless for separating aggressive cancers from others that are so slow-growing they will likely never cause problems.But a new blood test, described this week in the journal Urology, could change all that. In a study of 385 men, the new test was able to distinguish BPH from prostate cancer, and it pinpointed men who were healthy, even when their PSA levels were higher than normal. It also did the reverse—singling out men with cancer, even when their PSA levels were low. It may also distinguish cancer confined to the prostate from cancer that has spread beyond the gland. And it...

Sometimes great ideas are born of desperation. For Seattle Mayor Greg Nickels, that sense of urgency developed in the winter of 2004-05, when the annual snowfall failed to materialize in the neighboring Cascade Mountains. That's a serious issue in Seattle, where melting snow feeds the city's reservoirs in the springtime and swells the river that supplies its hydroelectric energy. Nickels's advisers were coming to him weekly with reports that the snow pack was just 1 percent of normal. "I don't think 'normal' exists anymore," Nickels remembers saying, having endured a succession of unusually warm winters. "Normal would be cause for popping champagne corks."Nickels wasn't the only one who was starting to worry about climate change. In February 2005, 141 nations worldwide were preparing to put the Kyoto Protocol into effect—aiming to reduce global warming by cutting greenhouse-gas emissions 7 percent below 1990 levels by 2012. The United States was notably not one of them, so Nickels...